The Maelstrom Mod introduces three new races to the Sins of a Solar Empire Universe. They are independent of the original races and have unique strengths and weaknesses. Maelstrom is available Rebellion, Diplomacy, Entrenchment and Original Sins.

The Swarm is conceptually a large number of specialized satellites around a star. The Sphere is conceptually a more enclosed structure around a star. The model for this (as seen above) is not finalized.